Degradation Analysis of α-Brass Drinking Water Pipes in Aggressive Soil

This study investigates the deterioration of water pipes made from two series of copper alloys, Ecobrass ۱ (E۱) and Ecobrass ۲ (E۲), when they are buried underground. Buried drinking water pipes often experience significant degradation, leading to a loss of drinking water. This degradation is influenced by climatic conditions, soil type, and the pressure due to depth. This study aims to determine the most suitable alloy for use in buried metal pipelines. The corrosion behaviour of Ecobrass in an aggressive soil environment was investigated using various methods. These included electrochemical impedance spectroscopy, polarization curves, and scanning electron microscopy coupled with an energy dispersive spectrometer (SEM-EDS). Additionally, an analysis was conducted using X-ray diffraction. The findings revealed that E۲ had the best corrosion resistance in the aggressive soil with the lowest corrosion current density and the lowest anodic current density. The corrosion products were primarily composed of metal oxides such as Cu۲O, CuO, and ZnO, with other compounds like SiO۲ also present on the surface of E۲. In comparison to E۱, E۲ demonstrated significantly better corrosion resistance in the Kenitra soil. These results provide compelling evidence to support the selection of E۲ as the preferred type of Ecobrass for use in buried pipes.

Keywords:

Eco-Brass , Dezincification , Aggressive Soil , Electrochemical tests , SEM-EDS , DRX